Art of handling fluent particles



July 21, 1953 Filed April 3o, 1948 R. C. LASSIAT ETAL ART OF HANDLING FLUENT PARTICLESv 4 sweets-sheet 1 INVENTORS RAI/mond GLA/:NAT

REZZBEH 7.' JZV GE W ATTO NEYv July 21, 1953' R. c. LAssfAT ETAL '2,646,407

ART OF HANDLING FLUENT PARTICLES Filed April 50, 1948 4 Sheets-Sheet 2 INVENTQRS R41/mand CLL/:fur

T'T RNEY July 21,1953 R. c. I AsslAT Erm. 2,646,407

' ART oF HANDLING FLUENT PARTICLES medpri; 3o, 194s 4 sheets-sheet s INVENTO RS l EAYmond (l LAdz/'IA T REuBEn 7.' :114141 6E i mlm July 21, 1953 R. c. LAsslAT Erm. v 2,646,407

ART 0F HANDLING FLUENT PARTICLES Filed April 5o, 1948 4 sheets-sheet 4 BY. @E

A ORNEY Patented July 21, 1,953 l T. Savage, Ridley Park, Pa., assignors to Houdry Wilmington, Del., a cor- Process Corporation, Vporation of Delaware Application April so, 1948, serial N. 24,238

The' use of moving bodies of fluent solidpar- Vticles in processes that involve the contact of f massesof such solid particleswith fluids, as, for example, catalytic conversions of organic vapors by solid catalystsgsuch as the catalytic cracking of hydrocarbons, has resulted in certainradvantages due to the continuous nature of the process but has also created problems arising from'the' 'nature of the process@ One such problem involving the introduction of the fluent so'lid particles to the contacting zone or chamber Vmay beV overcome by using methods and apparatus embodyving the present invention.y y

An obviously desirable and sometimes essential condition for the uniform contact of a contact mass or body of solid particles with a fluid in a contacting zone is that the body lof particles be uniform in average size'over the cross `sectional area of the body normal to the direction of flow of the fluid since otherwise the flowof the fluid through various portions of the-bodyis unequal with resultant .inequalities'in the timelof contact or extent of treatment or both and, if heat feffects are'present, with resultant vinequalities in the temperature of various portions of the body.

Such effects are particularly noticeable whenfthe body of solid particles is a non-turbulent bed which moves downwardly under the inuence of gravity as essentially a fluent mass or bed of particles.

Such a condition often occurs when the operation of the process continues over an extended period of time because of the development, Vby

' attrition, of a range of particle sizes even though the particles constituting the original contact mass were initially of the same s'ize, whichV is not always the case dueto variations encountered other factor contributing to the variation in V particle size is the common practice of adding percent of particles smaller than l mesh ink addition to material in the original range after six months of operation. (Percentages given herein are on a weight basis unless otherwise specified.)

It is known that a mass of fluent solid par- 11 Claims. (01252-411) ticles varying in size has a tendency to segregate so'as to develop portions containing predominantly particles Vof larger size and other portions containing predominantly particles of smaller size when subjected to ow down an inclined path (i. e.,lowing"a mass of such particles' down an inclined path results in an non-uniform dis,-

tribution of particles of the same size over the cross section of said mass normal to the direction ofv flow even Vthough the mass originally had a uniform distribution'in respect to particle size).

in a relatively small zone (asV from a pipe) above the top or apex ofra relatively large body orV pile Vof suchparticles, when therupper surface ofthe body is free or unrestricted and hence inclined in the manufacture of the solid particles. Anv of solid'particles. vlarger particles apparently roll down the-free at the free angleV of reposefof the solid particles Vwith the horizontal so that the particles flow or roll down the .free upper-surface. K A Y The latter condition obtains when a stream -of solid particles is fed to a contacting zone Whose lateral l crossr sectional area is considerably greater than the Vcross sectional area of the supplying stream and is exemplied in most contacting vessels containing moving non-turbulent beds Under these conditions, the

upper surface of the'pile (this free upper surface being roughly conical) at a faster rate than do the smaller particles. At any event, experiment has shown that the nest particles tend to accumulate directlyV below the point of discharge and that the average particle size increases in a direction radial from the vertical line on which the point of discharge lies, the largest particles thereby being concentrated at the periphery of the pile. It is therefore obviously undesirable to supply solid particles to the top of a nonturbulent bed of solid particles as a single stream` of restricted cross section. Y

Moreover, when introducing solid particles'to a contacting zone it is preferable, because of possible variations in the supply rate, to have a supply chamber containing a body or pile of solid Y particles, from which chamber the solid particlesv are fed to the contacting zone and which has sufficient capacity to maintain a constant rate of now of solid particlesto the contacting zone during variations in the rate at which the solid particlesare fed to the supply chamber If, however, the solid particles are discharged as streams located at points evenly distributed over the bottom of the pile of solid particles in the supply `chamber (i. e., the points of discharge are located ly constant distribution of the particles of the i same size is effected over substantially the entire cross sectional area of said contactingr zone by supplying said particles to a relatively small zone at the top of a body or pile of said particles in a supply chamber located above the contacting zone and of substantial lateral extent. The supply chamber is adapted to confine the body of particles at its sides and bottom vwhile allowing the upper surface of the body to be free so that it is'inclined at the free angle of repose. The supply lchamber is provided with outlets individually'communicating with theopen upper ends of downwardly directed conduits for discharging the particles from the 'bottom of the body as a multiplicity of solid streams. The outlets are arranged at points spaced equidistantly away from the vertical axis of the center of said body and, as explained below, thereby discharge streams of particles having the same distribution of particle size V(i. e., the vaverage particle size is approximately thev same). These outlets are also arranged and located so that the solid streams in the downwardly directed conduits averagely travel small lateral distances to the points of dischargalocated as described below.

The points of discharge, several of which may be associated with a single outlet from the supply chamber, are each at the center of one of a multiplicity of equal area subdivisions of at least the major portion of the transverse cross sectional area of the contacting zone. Each point of discharge is associated with an individual solid stream of particles which discharges froml the open lower end of a conduit in a restricted zone e at the top of a relatively small body or pile of particles, the size of this 'body Ybeing 'only a small fraction of the size of the body in the supply chamber and the lateral area of this body being only a small fraction of the lateral area of the contacting zone. The various relatively small bodies of particles are confined at the sides and bottom by individual receptacles which 'are located below and spaced apart'frcm the lower open ends of the conduits for discharging the individual solid streams of particles as described herein. The bottoms of the receptacles are provided with outlets spaced equidistantly away from the center thereof, these outlets being substantially equidistantly spaced from each other. By means of conduits which are individually associated with each outlet from a receptacle and which communicate with the contacting chamber or zone, the solid particles are introduced to the contacting zone as a considerable multitude of relatively small streams of catalyst having approximately the same distribution of particle size whereby approximately constant distribution of particles of the same size is eifected over the cross sectional area of the contacting zone.

The principles involved in the present invention are set forth in detail below in connection with the description of the drawings in which various preferred embodiments of the present invention are show-n. It is to be understood that sli) these preferred embodiments are to be regarded as illustrating the present invention rather than as restricting its scope. In the drawings:

Figs. 1, 4, '7 and 1l are vertical views of the upper portions of vessels containing moving beds of solid particles with portions of the vessels broken away for a better view of the relationship of the parts;

Figs. 2 and 3 are transverse sections of the vessel illustrated in Fig. l taken along the lines 2 2 and 3 3 respectively, showing the relationship of the parts of the apparatus at these levels.

Figs. 5 and 6 are transverse sections of the vessel illustrated in Fig. 4 along the lines 5 5 and 6 6 respectively, showing the relationship of the parts of the apparatus at these levels;

Figs. 8, 9 and 10 are similar transverse sections of the vessel shown in Fig. '7; and

Figs. 12 and 13 are similar transverse sections of the vessel shown in Fig. 11.

Shown in Fig. 1 is a closed housing or vessel indicated generally at 20 containing a downwardly moving non-turbulent bed of solid particles 2l which are contacted with fluids as described below. Solid particles are introduced to the housing by means of pipe or conduit 22 which Vcontains a stream of particles only partially filling it and from which the stream of particles discharges at the top or apex of a large body or n pile 23 of solid particles in a relatively small zone l(i. e., the diameter of the stream of particles impingingron the top of the body or pile is relatively small in respect to its lateral extent). The body of particles is of substantial lateral extent and is conned by the sides 2d of housing 2U, w-hich may be lined with a refractory lining 25 and covered by a layer of insulation 25, and by plate 2l' which is supported within the housing by beams 28. The sides 2li and plate- 2l thus form a supply chamber (indicated generally at 2S) located above the contacting zone (wllich comprises all or a part of bed 2l as described below) and within the housing, which supply chamber contains bed 23. 29 has sufficient capacity so that body 23 does not completely ll it, the upper surface of body' 23 being free and therefore inclined to the horizontal at the free angle of repose of the solid particles of which the body is composed.

As stated above, body 23 and hence supply chamber 29; are of substantial lateral extent, thus providing room for a multiplicity of outlets 3K3, whose function is described below. In the embodiment of the invention shown in Fig. l, the supply chamber is Within housing 2Q and is of Videntical lateral extent as the lateralv extent of bed 2l in the contacting zone. In other phases ofthe invention, such as in Fig. 7 where the supply chamber is outside the housing, the lateral extent of the body of solid particles and of the supply chamber may be different from the lateral extent of the contacting zone. In such cases, the lateral extent of the bed 2l and of the supply chamber 29 are approximately of the same order of magnitude, generally being less than one and one half and more than one third times the lateral extent of the contacting chamber of the contacting zone.

Solid particles are removed from the bottom of of the body 23 as a multiplicity of solid streams of particles through a multiplicity of outlets @Il in the bottom of chamber 29, which outlets individually communicate with the open ends of conduits 3|. (The term solid streams is Aused in the sense that the conduit is completely filled Preferably, chamber cated in a planeabove 2i.

` with solid particles.) The outlets are protected l are arranged equidistantly awayfrom the center of body 23 which is on the same Vertical line as the point of discharge from conduit 22 so that the locus of the outlets forms a circle whose center is the center of supply chamber 29. Outlets33 are preferably arranged at approximately regular intervals around the circle thus providing a symmetrical distribution, although in some instances it is necessary to avoid beams 28 which support plate 27. In general, the radius of the circle on which the outlets 3|] lie is approximately one half to two thirds of the average distance between the center of the chamber and the sides therer of. In any event, they arearranged so as to provide averagely small lateral distances `of. travel between the upper and lower ends of conduits 3|.

When the average lateral distances between the upper and lower endsof conduits. 3| is'small, the solid particles therein are subjectedto only a short distance of travel down an inclined path and'hence segregate as little as possible in a direction normal to theaxis of the conduit.V

As noted above, when a stream of solid particles is discharged on the top or apex of a body of particles such as body 23 as described herein, the particles tendto move outwardly from the center of the body in a regular manner.y One consequence of this behavior is that the particles in any circular annulus concentric with the center of the body have*approximatelythesame distribution in particle size. AIt is therefore apparent that the catalyst discharged 'from the bottom of body 23 through outlets 3 will have the same particle size distribution. Moreover, it has been foundY experimentally, that although initially the average particle size increases ina radial direction fromthe center of the body, under equilibrium conditions such as are encountered when the process has beenunder operation for some time, the size distribution of vthe lparticleswithdrawn through the outletswill be the same as that supplied to the top of the body. Apparently the catalyst initially segregates when the body is formed and thereafter the material supplied to the top of the body followsv such a path downwardly through the bed that the solid particles withdrawn from the bottom inthe man` ner described have not segregated, theinitially segregated particles remaining static.

As may be seen in Fig. 3, the lower ends of conduits 3| are disposed individually at Vthe centers of a multiplicity of equal area rectilinear subor apexes of a multiplicity of relatively small` bodies of particles 32a held in receptacles 33 loplaced concentrically below the open ends of conduits 3| and are spaced apart therefrom by rods 34 at such a distance thatV the relativelyv small body of vparticles in'each receptacle is conned by the sides and bottom of each receptacle, thus leaving the upper surface of each relatively small body of particles free and inclined at the free angle of repose of the solid particles except where the top of the body engages the open vlower end of conduit 3|.` Rods 33 are aiixed to conduits 3| as by welding and may extend through Aand be bolted to receptacles 33 by nuts 35 or may be aixed to basketsor receptacles 33 as by welding. The relative positionsV or theiindvidual re- Receptaclesr 33 are laraiofr 'Y on the upper surface of bed 2|..

. ceptacles are maintainedrby spacers 36 which are aiixed, as by welding, to the receptacles as shown. VEach of receptacles 33, which are in the form of square open top boxes or baskets', has a plurality of outlets 3'| in the bottom thereof, these out-v lets individually communicating with conduits 38. These outlets are arranged equidistantly vfrom the center of each receptacle and substan. tially'equidistantly and symmetrically in respect to each other. receptacle are shown in Fig. 3, a smaller number, preferably not less than three or a greater number such as six or more may be used.

vAs can be seen from Fig. l, the solid particles in each of bodies 32a are discharged as a plurality of relatively small solid streams of. particles (conduitsSS being of smaller diameter than conduits 3|), these solid streams being discharged The receptacles 33 and conduits '38 thereby constitute a means,

associated with conduits 3|, for vdischarging a multiplicity of small streams Yofsaid Vparticles utor (not shown).

. ing by conduits 43, the flow of fluid in conduits area of said bed. It is to be noted that thezpar-i ticles in conduits 38 have substantially the'same distribution of particles due to the yarrangement of the conduits in respect to bodies 32a due to the eect explained above.

In the embodiment of the invention shown in Figs. l, 2 and 3 the contacting chamber is rectilinear in transverse cross section. Means are'thus aiorded by theginvention for passing particles of the same size range from' a circular pattern of distribution (outlets 30 in supply chamber 29) to a rectilinear .patternv of'distribution (conduits- 33). The change in the pattern of distribution is more` readily apparent in the embodiment illustrated in Figs. 7, 8, 9 andi l0, Where the supply chamber is circular in transverse cross section and the contacting zoneis rectilinear. As shown by Figs. l1, l2, 13A and 14, the invention may also be used where the contacting chamber is circular in transverse cross section.

In the embodiments shown in Figs. vl, 4, 7 and l 11 the bed of solid particles so formed may be used for contacting iiuids such as vapors or gases in several ways; for example, a portion of the fluids introduced by conduits 39 and vapor distributor 4| may pass partiallyupwardly through the bed and partially'downwardly through the` bed, the latter portion then being removed by conduit 42 which is connected to a Vapor distrib- The portion of fluid passingv upwardly passes Vthrough the upper surface of the bed'and is thereafter removed from the hous-.z

43 beingcontrolledby butterfly valves 44.' The' iluid removed by conduits 43 passes to manifolds 45 and thereafter to suitable uses or to a disposal system depending on -the nature of` the fluid. Alternatively, fluids may be introduced by conduits 39 and removed by conduits 42, only a small portion of the `vapo-rs passing throughthe upper;

Although four outlets from each discharge of particles `from the housing is preferably controlled to effect the desired rate of downward travel of the particles in bed 2 i. After discharge from the contacting zone, the particles may travel through one or more zones including a regeneration or reactivation zone for restoring any properties changed or modified by the cntact of the particles with fluids in housing 2li or through a reaction zone if the operation in housing has been that of regeneration and are thereafter elevated to the top of housing 20' and fed thereto, thus completing one cycle of operation.

The vessel or housing shown in Fig. 4 is constructed and arranged similarly to housing 25 shown in Fig. l and is likewise indicated generally as 20. Parts in housing 20 shown in Fig. 4 which are the same as parts in Fig. l have been given the same numbers. In general, the solid particles fed to housing 2d in Fig. 4 by conduit 22 travel therethrough in a manner similar to that described in connection with Fig. l.

In the embodiment shown in Fig. 4 the conduits throughwhich the particles from'bed 23 travel comprise two sets of conduits 50 and 5I. However, outlets in plate 2l with which the open ends of both sets of conduits 5i] and 5| individually communicate are arranged in a similar fashion to outlets 30 in Fig. l and have therefore been similarly designated.

One set of conduits 5l! is associated with a multiplicitj7 of receptacles 3d which together with conduits 38 constitute a means for discharging particles as a multiplicity of small streams of said particles symmetrically and regularly located at small intervals over the majority of the transverse cross sectional area of housing 2li in the manner described above as can be seen in Fig. 6.

Conduits 5i, which are the remainder of the conduits associated with outlets 3Q, extend downwardly to points spaced regularly around inside wall 24 and spaced immediately above bed 2i. The open lower ends of conduits 5E communicate individually with discharge nozzles 52. Discharge nozzles-52 terminate in flared, flattened lower ends as can be seen from Figs. 4 and 6 and are thereby adapted to discharge a layer of particles substantially uniform in size adjacent to wall 24.

It will be noted that conduits 5d communicate with a. substantial portion of outlets 3G while conduits 5I communicate with the remainder. Conduits 5t and 5| may be of the same or different diameters and the ratio of the number of conduits comprising one set to the number comprising the other set may be varied within rather broad ranges so long as the conduits perform their function of conveying the solid particles to the designated locations. The relation of the two sets of conduits, the diameter of the conduits and similar factors are generally selected by the design engineer in accordance with functions of the apparatus not directly involved in the present invention, such as pressure drop, seal leg effects and the like. It is, however, preferred' that the set of conduits 5i) comprise at least a substantial portion of the conduits fed by the particles from body 23.

In regard to Figs. 4, 5 and 6, it is to be noted that the embodiment of the invention described in connection therewith furnishes a method for supplying a multiplicity of relatively small streams of particles having the same distribution of particle size regularly over the entireV transverse cross sectional area of bed 2l with special provision for the discharge of such streams adjacent to wall 24. Because of the disposition of Y conduits 5l and nozzles 52 and the shape of nozzles 52, the point of discharge of the solid stream of particles is quite close to wall 24 and there is scant opportunity for the particles so discharged to roll any considerable distance toward the Wall. The advantage of such method is appreciated when consideration is given to the fact that, if the particles rolled a considerable distance toward the wall (as would occur if the top of the pile or the point of discharge were spaced away from the wall a considerable distance), segregation would result. The embodiment described above thereby prevents segregation in the layer of particles adjacent to the wall of the housing.

In the embodiment shown in Figs. 7, 8, 9 and l0, a supply chamber 60 is located outside and above a closed housing indicated generally at 6i, which, like housing 2B, comprises a contacting zone. or chamber containing a bed of solid particles 62. Supply chamber G0, which is circular intransverse cross section, has outlets 63 in the bottom thereof for discharging solid particles from the body or pile of particles 6d contained therein; these outlets being arranged and located in a similar fashion to outlets described above. Solid particles discharge from body 54 and travel downwardly in conduits 65 as solid streams in the fashion described above in connection with conduits 3l except as described below. Conduits v65 extend downwardly from chamber 6G, through and below the top of housing GI, to points spaced above and apart from bed 62, a majority of conduits S5 terminating for the most part in closed lower ends. Immediately above such closed lower ends are openings in conduits 65 ccmmunicating with smaller branched conduits GB which extend downwardly to individual receptacles Sl constructed and disposed as described above in connection with receptacles 33. Branched conduits B6 subdivide a substantial portion of the streams in conduits 55 into smaller solid streams directed to receptacles Sl. Receptacles 61 are placed concentrically below the discharge ends of conduits 66 and spaced apart therefrom as described above. Conduits B8, which are branched conduits close to the wall 24, are tted with discharge nozzles 52 of the type described above in connection with the embodiment illustrated in Fig. 4. In a few cases, conduits 65 communicate directly (i. e.. without branched conduits) with receptacles Eil. In an alternate design, all of conduits 65-com municate with branched conduits.

In the embodiment shown in Fig. 7, conduits 59 communicating with the outlets of receptacles 6l are constricted at their lower ends or alternatively may be of such a diameter that the collective discharge capacity of theseiconduits is less than that of the conduit feeding the individual receptacle associated with each set of conduits 69. As a consequence the level of bed 62 may be substantially below the discharge ends of conduits 69 so that freely falling streams of particles discharge from conduits 59 and thereafter fall freely downwardly to the surface of bed 62. When such a relationship exists between conduits 66 and the conduits E9 associated with the individual receptacles, the depth or height of bed 62 may be varied without altering the position of receptacles El as would be necessary if the discharge rate from receptacle 6l were greater than the feed rate so that a Ythetop of the bed 62 is contiguous with the lower ends of conduits 69 (as is the case in Fig. 1), the rate of iiow through any of conduits 69, 6 6 or 65 is determined by the rate at which the bed is discharged from the bottom of the housing. Ink such a case, although conduits 69 may conveniently be of smaller diameter than conduits 66 or 65, they are not necessarily so and where,

in the specification and claims, the solid streams of catalyst in conduits 69 and in conduits performing similar functionsvare referred to as having smallerA diameters than the solid streams in conduits 66 or 65, itis in the sense that the rate of flow in the former is smaller than the rate of flow in the latter.

Shown in Fig. 11 is another embodiment of the present invention in whichthe housing containing the contacting zone is circular in transverse cross section (indicated generally as 70).

Supply chamber 1l is circular in cross section andthe bottom is provided with two sets of outlets 12 and 13 which are arranged in a circle in the manner described above. Two sets of conduits 14 and 15 are associated with the two sets of outlets 'l2 and 13 respectively.

The set'of conduits designated as 12 are of smaller diameter than the set of conduits designated as 'I3 and communicate with nozzlesrl' arranged regularly around the periphery of bed of particles Tl as shownin Fig. 14. The other set of conduits 15, which `are larger in size, :communicate with smaller conduits 18, which smaller conduits have openlower ends spaced concentricall'y above hexagonally shaped receptacles 79 in the manner .described above. Receptacles 'I9 l are provided with outlets communicating with. conduits or pipes 80 arranged and disposed in forms of apparatus for accomplishing the pur- .f

range of from more than about 0.01 to less than about 0.5 inch, the ratio' of the largest`5 percent of such particles to the smallest 5 percent generally being less than vabout 20 to 1 and preferably betweenabout 5 to 1 and 10 to l. Such particles may be fed by the methods described above, using the same or similar apparatus, to.

either a cracking zone for contact therein with hydrocarbon fractions, such as fractions boiling pose of'feeding solid particles of uniform size distribution to a contact zone. A contact zone such as that involved in the present invention maybe employed for variety of purposes and processes. Thus the present invention will be found useful inthe eld of hydrocarbon conversion processes elfected by the contact of hydrocarbon fluids with solid catalysts such as the operationsof cracking, reforming, hydroforming, hydrogenation, desulphurization, vis-breaking andthe like or in the field of processes using inert granular contact masses which may be porous orvrelatively impervious such as thermal vis-breaking with an inert mass, thermal cracking of hydrocarbon oils to gases, heat transfer and the like. 4' l Exemplary of such processes is the hydrocarbon catalytic cracking process. In accordance with the present invention, the bulk of the solid catalyst Yparticlesare preferably within a size above gasoline, at cracking temperatures in the range of 650 t0 '1100 F., or catalyst which has been coked (i. e., accumulated a hydrocarbonaceous deposit) as a result of contact with hydrocarbon fractions in a cracking operation may be fed to a regeneration zone to be contacted therein with a combustion supporting gas for the removal of a portion or all Vof the coke deposited on the catalyst. Processes involving such cracking and regeneration operations are well known to the art; for example, a description of a typical process related to the present invention is set forth'in The T. C. C. Cracking vProcessfor Motor Gasoline Production by R.

HfNewton, G. S. Dunham and T. P. Simpson, Transactions of the American Institute .of Chemical Engineers, volume 41, page 215, April 25, 1945, and in the articles there cited.

It has been found that, in the operation of commercial size plants, excellent results Vare Ob- 1 tained with particles of the'size described above when the conduits discharging the catalyst 0n Vthe top of the bed in the contacting zone are spaced between 4 to 18 inches apart.

Contact masses for such processes may consist of appropriately sized particles of natural or artificial aluminosilicates, the latter being of the synthetic gel type, or other synthetic gel cracking catalysts such as catalystscontaining silica and other refractory oxides. Typical contact masses from natural .products are described in U. S. Patent 2,078,945, issued on May 4, 1937', to E. J. Houdry and from synthetic gels in U. S. Patent 2,429,981, issued on November4, 1947, to J. R. Bates.

n other processes of the heat transfer or with resultant increases of yield of the desired,

products of the cracking reaction or in superior control of the regeneration voperation with resultant economies inV catalyst life and/or rapidity? of regeneration. Also due to the inv crease in eiiiciency of `Contact, higher rates of throughout vbemaintained and valuable economies inoperation may thereby be effected.

vObviously many modifications and variationsV of the invention as hereinbefore'setforth may be made without departingl from the spirit and scope thereof Iand therefore only such limitations should-be imposed as areindicated inthe appended claims.

VWe claim as our invention:

l.. The process for the introduction'into a fluid of said particles down an inclined path results in a non-uniform distribution of particles of the same size over the cross section oi said mass normal to the direction of flow which comprises supplying said particles to a relatively small laterally-xed zone of deposit at the top of a body of said particles located a substantial distance above said contacting zone and having a free upper surface inclined downwardly from said zone of deposit at the free angle of repose of said particles, discharging said particles from the bottom of said body simultaneously7 as a multiplicity of solid streams of said particles whose inlets are located on a circular locus about the vertical central axis of said body, directing at least the major portion of said solid streams of discharged solid particles downwardly and laterally to a multiplicity of points uniformly distributed over the upwardly projected horizontal cross-sectional area of the contacting zone, discharging each of said solid streams at the top of `a relatively small body ofV said particles in a zone small in relation to said contacting zone, each of said relatively small bodies being supported in lateral connement above the contacting zone and having a free upper surface, and discharging particles from each of said relatively small bodies solely as a plurality of vertical solid streams of said particles at points uniformly distributed along a circumference whose center is on a vertical axis through the center of said relatively small body whereby approximately ccnstant simultaneous distribution of particles of the same size is eiected over said horizontal cross-sectional area of said contacting zone.

2. The process for the introduction of fluent solid particles varying in size over a range such that flowing a mass of'said particles down an inclined path results in a non-uniform distribution of yparticles of the same size over the cross section of said mass normal to the direction of flow into a zone containing a downwardly moving bed of said particles which comprises supplying said particles to a relatively small laterally-fixed zone of deposit at the topl of a body of said particles located a substantial distance above said contacting zone and having a free upper surface inclined downwardly from said zone of deposit at the free angle of repose of said particles, discharging said particles from the bottom of said body simultaneously as a multiplicity of solid streams of said particles whose inlets are located on a circular locus about the vertical central axis of said body, directing a majority of said solid streams of discharged particles downwardly to a multiplicity of points uniformly distributed over the central and major portion of the surface of said bed of particles, directing the remaining solid streams of particles to locations regularly arranged around the periphery of said last-mentioned surface, and flowing the particles in said remaining streams onto the surface of said bed as a peripheral layer, whereby approximately constant simultaneous distribution of particles of the same size is effected over all of the horizontal cross-sectional area of said contacting zone.

V3. The process for the introduction into a fluid contacting zone of fluent solid particles varying in size over a range such that flowing a mass of said particles down an inclined path results in a non-uniform distribution of particles of the same size over the cross section of said mass normal to the direction of flow which comprises supplying said particles to a relatively small laterally-iixed zone of deposit at the top of a body of said particles located a substantial distance above said contacting zone and having a free upper surface inclined downwardly from .said zone of deposit at the free angle of repose of said particles, discharging said particles from the bottom of said body simultaneously as a multiplicity of solid streams of said particles whose inlets are located on a circular locus about the vertical central axis of said body, directing said multiplicity of solid streams downwardly to points spaced above said contacting zone, subdividing at least a majority of said solid streams into smaller streams, directing said smaller solid streams downwardly and laterally to a multiplicity of points uniformly distributed over the upwardly projected horizontal cross-sectional area of the contacting zone, discharging each of said -smaller streams at the top of a relatively small body of said particles in a zone small in relation to said contacting zone, each of said relatively small bodies being supported in lateral coniinement above the contacting zone and having a free upper surface, and discharging particles from each of said relatively small bodies solely as a plurality of vertical solid streams of said particles at points uniformly distributed along a circumference whose center is on a vertical axis through the center of said relatively small body whereby approximately constant simultaneous distribution of particles of the same size is effected over said horizontal cross-sectional Varea of said contacting zone.

4. The. process for the introduction of iluent solid particles varying in size over a range such that flowing a mass of said particles down an inclined path results in a non-uniform distribution of particles of the same size over the cross section of said mass normal to the direction of now into a zone containing a downwardly moving bed of said particles which comprises supplying said particles to a relatively small laterallyfixed zone of deposit at the top of a body of said particles located 'a substantial distance above said contacting zone and having a free upper surface inclined downwardly from said zone of deposit at the free angle of repose of said particles, discharging said particles virom the bottom of said body simultaneously as a multiplicity of solid streams of said particles whose inlets are located on a circular locus about the vertical central axis of said body, directing a portion of said solid streams of discharged particles downwardly and laterally to a multiplicity of points uniformly distributed over the central and major portion of the horizontal surface of said bed of particles, directing the remainder of said solid streams of discharged particles downwardly and laterally to `locations regularly arranged around the peripheral surface of said bed, discharging each of the centrally directed solid streams onto the top of a'relatively small body of said .particles in a zone small in relation to said contacting zone, each of said relatively small .bodies being supported in lateral confinement above the contacting zone and having a free upper surface, discharging particles from each of said relatively small bodies solely as a plurality of Vertical solid streams of said particles at points uniformly distributed along a circumference whose -center is on a vertical axis through the center of said relatively l small body, and iiowing the particles in the peripherally directed solid streams onto the surface of said bed as a layer adjacent the pe- A. cracking catalyst and in which said fluid contacting zone is a zone in which hydrocarbon fluids contact said fluent solid particles of hydrocarbon crackingv catalyst.

6. The process of claim 1 in whichsaid fluent solid particles are particles of hydrocarbon cracking catalyst bearing a hydrocarbonaceous deposit as the result of vprevious use in the conversion of hydrocarbons and in which said particles contact acombustion-supporting gas to effect regeneration of said catalyst in said contacting zone.

7. In apparatus for the contact of solid particles and fluids in a contacting chamber, said apparatus comprising a closed housing containing said contacting chamber, means for the removal of said solid particles from said contacting chamber and from said housing, means for the introduction of fluids to said housing and said contacting chamber, and means for the removal of saidfiuids from said housing and said contacting chamber, the vcombination thereof with a supply chamber adapted-to contain a large body of said' particles and located above saidk contacting chamber,A said supply chamber having a multiplicity of outlets in the bottom thereof located at points the locus of which'isv a circle whose center is on the vertical axis of said supply chamber and whose radius is approximately half the average distance between said axis and the sides of said supply chamber,

Y said outlets being uniformly spaced along said circle, amultiplicity of conduits communicating with said outlets and extending downwardly from said supply chamber into said housing, a substantial number of said conduits being provided at their lower ends with means for discharging solids at a plurality of locations distributed uniformly over the major portion of the horizontal cross-sectional area of said contacting chamber, the remainder of said conduits having their lower endsl located at regularly l14 and positioned above said contacting chamber, the Ycenter of each of .said receptacles being at a point located at the center of one of a multiplicity of approximately equal varea subdivisions Vof at least the major portion of the transverse cross sectional area of said contacting chamber, a multiplicity of open' end conduits communicating with a substantial portionof the-outlets from the supply chamber and extending downwardly below said supply chamber to points immediately above said receptacles, each receptacle being associated with the open lower endof one conduit, each of said receptacles being arranged concentrically below the open lower end of each conduit at such af distance that solid particles ldischarging from saidlowerV end form a body of particles extending laterally to the sides of said receptacle and vertically to the lower end of the conduit thereabove, each of said receptacles having a plurality of outlets in the bottom thereof arranged equidistantly from the center of said receptacles and substantially symmetrically in respect to each other, and conduits individuallyv communicating with each outlet from said receptacles and extending vertically below said receptacles and communicating with said contacting chamber as means for introducing said particles to said chamber.

9. In apparatus for the contact of solid particles and fluids in a rectilinear' contacting chamber, said apparatus comprising a closed housing containing said contacting chamber, means for the removal of said solid particles from said contacting chamber and from said housing, and means for the introduction of'fluids to said housing and t0 said contacting chamber,

and means for the removal of said fluids from said housing and from said contacting chamber, the combination thereof witth a supply chamber adapted to contain alarge body of said particles and located above said contacting chamber and within said housing, said supply chamber having a multiplicity of outlets in the bottom thereof, thelocus of the centers of said outlets being a circle whose center is the center of said supply chamber andY whose radius is between approxi- Y mately half to two thirds ofV the average dising said contacting chamber, means Vfor the removal of said solid particlesfrom said contacting chamber andfrom said housing, and means for the introduction of fluids to said Yhousing and to said contacting chamber, and means for the removal of said fluids from said housing and from said contacting chamber, the combination thereof with a supply chamber adapted tocontain a large body of said particles and lc- Vcated above said contacting chamber, saidsupply chamber having a multiplicity of outlets in the bottom' thereof, the locus of the centers of said outlets being a circle whose center is the center of said supply chamber and whose radius apart from the bottom of said supply chamber tance between the center of saidsupply chamber and the sides thereof, said outlets being arranged at'substantiallyregular intervals around said circle, a multiplicity of open top receptacles positioned below and spaced apart from the bottom of said supply chamber and positioned above said contacting chamber, the center of `each of said receptacles being at a point located at the center Vof one of a multiplicity of approximately equal area rectilinear subdivisions of at least the major portion of the transverse cross sectional area of said rectilinear contacting chamber, a multiplicity of open end conduits communicating with a, substantialportion of thel outlets from the supply chamber and extending downwardly below said supply chamber to points immediately above said receptacles, each, receptacle beingassociated with the open lower end of one conduit',V each of said receptacles being arranged concentrically below the open lower end of each conduit at such a distance that solid particles discharging from .said lower end form a body of particles extending laterally to the sides of said receptacle and'verticallyto the lower end of the conduit thereabove,-each of said receptacles having a plurality of outlets in the bottom thereof arranged equidistantly from the. center of said receptacle and substantially symmetrically in respect to each other, and con- 15 duits individually communicating witheach outlet from said receptacles and extending vertically below said receptacles and communicating with said contacting chamber as means for introducing said particles to said chamber.

10. In apparatus for the contact of solid particles and iluids in a contacting chamber, said apparatus comprising a closed housing containing said contacting chamber, means for the removal of said solid particles from said contacting chamber and from said housingy means for the introduction of iiuids to said housing and to said contacting chamber, and means for the removal of said fluids from said housing and from said contacting chamber, the combination thereof with a supply chamber adapted to contain a large body of said particles and located within said housing and above said contacting chamber, said supply chamber having a multiplicity of outlets in the bottom thereof, the locus of the centers of said outlets being a circle whose center is the center of said supply chamber and whose radius is between approximately half to two thirds of the average distance between the center of said supply chamber and the sides thereof, said outlets being arranged at substantially regular intervals around said circle, a multiplicity of open top receptacles positioned below and spaced apart from the bottom of said supply chamber and positioned above said contacting chamber, the center of each of said receptacles being at a point located at the center of one of a multiplicity o approximately equal area subdivsions of substan tially the entire transverse cross sectional area of said contacting chamber, a multiplicity of open end conduits individually communicating with the outlets from the supply chamber and extending downwardly below said supply chamber to points immediately above said receptacles, each receptacle being associated with the open end of one conduit, each of said receptacles being arranged concentrically below the open lower end of eachfconduit vat such a distance that solid particles discharging from said lower end iorm a body of particles extending laterally to the sides of said receptacle and vertically to the lower end of the conduit thereabove, each of said receptacles having a plurality of outlets in the bottom thereof arranged equidistantly from the center of said receptacle and substantially symmetrically in respect to each other, and conduits `tiplicity of open l5 tacting chamber, and means for the removal of said uids from said housing and said contact* ing chamber, the combination thereof with a supply chamber adapted to contain a large body of said particles and located above said contacting chamber, said supply chamber having a multiplicity of outlets. in the bottom thereof, the locus of the centers of said outlets being a circle whose center is the center of said supply chamber and whose radius is between approximately half to two thirds of the average distance between the center of said supply chamber and the sides thereof, said outlets being arranged at substantially regular intervals around said circle, a multop receptacles below and spaced apart from the bottom oi said supply chamber and positioned above said contacting chamber, the center of each of said receptacles being at a point located at the center of one of a multiplicity of approximately equal area subdivisions of at least the major portion of the transverse cross sectional area of said contacting chamber, a multiplicity of open end conduits communicating with a substantial portion of said outlets from the supply chamber and extending downwardly below said supply chamber to points spaced above said receptacles, a plurality of conduits communicating with at least a majority of each of said conduits from. the supply chamber for subdividing the streams of solid particles in each conduit into a plurality of streams and eX- tending downwardly to points immediately above said receptacles, each receptacle being associated with the open lower end of a conduit and arranged concentrically therebelow at such a distance that solid particles discharging from said lower end form a body of particles extending laterally to the sides of said receptacle and vertically to the lower end cf the conduit thereabove, each of said receptacles having a plurality of outlets in the bottom thereof arranged in a manner similar to the arrangement of the outlets from said supply chamber, and conduits individ ually communicating with each outlet from said receptacles and extending vertically below said receptacles and communicating with said contacting chamber as means for introducing said particles to said chamber. l

RAYMOND C`. LASSIAT. REUBEN T. SAVAGE.

References Cited in the le of this patent UNITED STATES PATENTS 

1. THE PROCESS FOR THE INTRODUCTION INTO A FLUID CONTACTING ZONE OR FLUENT SOLID PARTICLES VARYING IN SIZE OVER A RANGE SUCH THAT FLOWING A MASS OF SAID PARTICLES DOWN AN INCLINED PATH RESULTS IN A NON-UNIFORM DISTRIBUTION OF PARTICLES OF THE SAME SIZE OVER THE CROSS SECTION OF SAID MASS NORMAL TO THE DIRECTION OF FLOW WHICH COMPRISES SUPPLYING SAID PARTICLES TO A RELATIVELY SMALL LATERALLY-FIXED ZONE OF DEPOSIT AT THE TOP OF A BODY OF SAID PARTICLES LOCATED A SUBSTANTIAL DISTANCE ABOVE SAID CONTACTING ZONE AND HAVING A FREE UPPER SURFACE INCLINED DOWNWARDLY FORM SAID ZONE OF DEPOSIT AT THE FREE ANGLE OF REPOSE OF SAID PARTICLES, DISCHARGING SAID PARTICLES FROM THE BOTTOM OF SAID BODY SIMULATANEOUSLY AS A MULTIPLICITY OF SOLID STREAMS OF SAID PARTICLES WHOSE INLETS ARE LOCATED ON A CIRCULAR LOCUS ABOUT THE VERTICAL CENTRAL AXIS OF SAID BODY, DIRECTING AT LEAST THE MAJOR PORTION OF SAID SOLID STREAMS OF DISCHARGED SOLID PARTICLES DOWNWARDLY AND LATERARLLY TO A MULTIPLICITY OF POINTS UNIFORMLY DISTRIBUTED OVER THE UPWARDLY PROJECTED HORIZONTAL CROSS-SECTIONAL AREA OF THE CONTACTING ZONE, DISCHARGING EACH OF SAID SOLID STREAMS AT THE TOP OF A RELATIVELY SMALL BODY OF SAID PARTICLES IN A ZONE SMALL IN RELATION TO SAID CONTACTING ZONE, EACH OF SAID RELATIVELY SMALL BODIES BEING SUPPORTED IN LATERAL CONFINEMENT ABOVE THE CONTACTING ZONE AND HAVING A FREE UPPER SURFACE, AND DISCHARGING PARTICLES FROM EACH OF SAID RELATIVELY SMALL BODIES SOLELY AS A PLURALITY OF VERTICAL SOLID STREAMS OF SAID PARTICLES AT POINTS UNIFORMLY DISTRIBUTED ALONG A CIRCUMFERENCE WHOSE CENTER IS ON A VERTICAL AXIS THROUGH THE CENTER OF SAID RELATIVELY SMALL BODY WHEREBY APPROXIMATELY CONSTANT SIMULATANEOUSLY DISTRIBUTION OF PARTICLES OF THE SAME SIZE IS EFFECTED OVER SAID HORIZONTAL CROSS-SECTIONAL AREA OF SAID CONTACTING ZONE. 